[PATCH v3 00/10] vfio_pci: wrap pci device as a mediated device

From: Liu Yi L
Date: Fri Nov 22 2019 - 06:42:08 EST


This patchset aims to add a vfio-pci-like meta driver as a demo
user of the vfio changes introduced in "vfio/mdev: IOMMU aware
mediated device" patchset from Baolu Lu. Besides the test purpose,
per Alex's comments, it could also be a good base driver for
experimenting with device specific mdev migration.

Specific interface tested in this proposal:
*) int mdev_set_iommu_device(struct device *dev,
struct device *iommu_device)
introduced in the patch as below:
"[PATCH v5 6/8] vfio/mdev: Add iommu related member in mdev_device"

Patch Overview:
*) patch 1 ~ 7: code refactor for existing vfio-pci module
move the common codes from vfio_pci.c to
vfio_pci_common.c
*) patch 8: add protection to perm_bits alloc/free
*) patch 9: add vfio-mdev-pci sample driver
*) patch 10: refine the sample driver

Links:
*) Link of "vfio/mdev: IOMMU aware mediated device"
https://lwn.net/Articles/780522/
*) Previous versions:
Patch v2: https://lkml.org/lkml/2019/9/6/115
Patch v1: https://www.spinics.net/lists/kvm/msg188952.html
RFC v3: https://lkml.org/lkml/2019/4/24/495
RFC v2: https://lkml.org/lkml/2019/3/13/113
RFC v1: https://lkml.org/lkml/2019/3/4/529
*) may try it with the codes in below repo
https://github.com/luxis1999/vfio-mdev-pci-sample-driver.git : v5.4-rc7-pci-mdev

Please feel free give your comments.

Thanks,
Yi Liu

Change log:
patch v2 -> patch v3:
- refresh the disable_idle_d3, disable_vga and nointxmask config
according to user config in device open.
- add a semaphore around the vfio-pci cap/ecap perm bits allocation/free
- drop the non-singleton iommu group support to keep it simple as it's
a sample driver for now.

patch v1 -> patch v2:
- the sample driver implementation refined
- the sample driver can work on non-singleton iommu groups
- the sample driver can work with vfio-pci, devices from a non-singleton
group can either be bound to vfio-mdev-pci or vfio-pci, and the
assignment of this group still follows current vfio assignment rule.

RFC v3 -> patch v1:
- split the patchset from 3 patches to 9 patches to better demonstrate
the changes step by step

rfc v2->v3:
- use vfio-mdev-pci instead of vfio-pci-mdev
- place the new driver under drivers/vfio/pci while define
Kconfig in samples/Kconfig to clarify it is a sample driver

rfc v1->v2:
- instead of adding kernel option to existing vfio-pci
module in v1, v2 follows Alex's suggestion to add a
separate vfio-pci-mdev module.
- new patchset subject: "vfio/pci: wrap pci device as a mediated device"


Alex Williamson (1):
samples: refine vfio-mdev-pci driver

Liu Yi L (9):
vfio_pci: move vfio_pci_is_vga/vfio_vga_disabled to header
vfio_pci: refine user config reference in vfio-pci module
vfio_pci: refine vfio_pci_driver reference in vfio_pci.c
vfio_pci: make common functions be extern
vfio_pci: duplicate vfio_pci.c
vfio_pci: shrink vfio_pci_common.c
vfio_pci: shrink vfio_pci.c
vfio/pci: protect cap/ecap_perm bits alloc/free
samples: add vfio-mdev-pci driver

drivers/vfio/pci/Makefile | 9 +-
drivers/vfio/pci/vfio_mdev_pci.c | 430 ++++++++++
drivers/vfio/pci/vfio_pci.c | 1460 +---------------------------------
drivers/vfio/pci/vfio_pci_common.c | 1471 +++++++++++++++++++++++++++++++++++
drivers/vfio/pci/vfio_pci_config.c | 33 +-
drivers/vfio/pci/vfio_pci_private.h | 39 +
samples/Kconfig | 11 +
7 files changed, 2000 insertions(+), 1453 deletions(-)
create mode 100644 drivers/vfio/pci/vfio_mdev_pci.c
create mode 100644 drivers/vfio/pci/vfio_pci_common.c

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2.7.4